We plan to expand the development and clinically validate a closed-loop functional neuroimaging system for the purpose of evaluating subjects with traumatic brain injury (TBI). The considered functional Diffuse Optical Tomography (fDOT) imaging system offers a comprehensive solution to the problem of exploring, in real-time, event related hemodynamic responses from essentially area of the head. Supporting this capability has been the development, under Phase I support, of a novel helmet design that can accommodate dense arrays of optical fibers and that can be quickly and easily adapted to comfortably examine essentially any head geometry. Complementing this capability has also been significant advances in instrument system capabilities and analysis software. Still another significant advance, has been the development of a programmable head-shaped calibrating phantom that can accurately mimic essentially any time-varying hemodynamic response with high fidelity and temporal accuracy. This capability is made possible through use of electrochromic materials whose optical properties can be rapidly and accurately modulated by adjustment of the driving voltage. By simply programming the Diffuse Optical Tissue Simulator (DOTS) phantom to mimic clinical findings of interest, true image features can be reliably distinguished from artifact. This unique and patented capability represents a significant advance in the effort to obtain objective and routine system validation of complex physiological states. The experimental plan calls for improvements to our data collection hardware and to update our instrument and analysis software in ways that (i) support examination of larger size data sets and (ii), permit mapping of image features to the underlying anatomy, and to follow this by a clinical study that will explore different aspects of executive function (working memory, language initiation) in healthy volunteers and subjects with TBI. These results will be analyzed to produce statistical maps of group differences for selected parameters from which we can derive composite measures based on multivariate analysis methods. Finally, we will independently validate the image results by comparing the fDOT image findings to fMRI and clinical findings, and to results obtained using our DOTS phantom. The plan development will complement our already advanced imaging system that has attracted growing demand for which systems are in use in eleven leading research centers world-wide. We are confident that the considered system design and capabilities will open a large market opportunity in support of clinical management of TBI and to the neuroscience community. [unreadable] [unreadable] Planned is the development of an inexpensive brain imaging system able to detect and monitor Traumatic Brain Injury, which affects 2.5-6.5 million people and costs an estimated 48.3 billion in the US each year. The core technology will be updated and preliminary results will be followed up with a clinical trial that focuses on analyzing brain function in TBI patients and healthy volunteers. In order to fully validate this technology, results of the clinical trial will be compared to fMRI experiments performed on the same patient population, as well as a dynamic phantom study. [unreadable] [unreadable] [unreadable]